Harvesters which are variously referred to as windrowers or windrower-conditioners normally perform a combination of several different, simultaneous operations on a hay crop during a single pass across a field, including mowing the standing crops from the field, feeding the severed materials between a pair of oppositely rotating conditioning rolls which crimp or bruise the plant stems to promote rapid curing, and redepositing the conditioned materials onto the ground in a windrow or swath. In some cases, the conditioning rolls are shorter than the width of cut taken by the header, requiring then that the cut materials be collected and gathered inwardly to some extent before they are passed rearwardly through a discharge opening which leads to the conditioning rolls.
It is a common expedient to use a center-gathering auger for this purpose. However, while such an auger performs adequately in many conditions, we have found that in certain situations relying upon a mere auger of that type to perform the gathering of severed materials for presentation to the conditioning rolls can lead to serious problems.
For example, as the difference between the cutting width of the header and the length of the conditioning rolls increases significantly, it has been noted that the tendency is for the entire mass of the laterally collected materials to immediately turn rearwardly upon reaching the opening and thus bunch up at that locatiom, causing the crop mat flowing between the rolls to be excessively heavy and thick at its opposite ends. This creates a significant lack of uniformity across the length of the conditioning rolls and, in turn, results in a lack of uniform conditioning action on the materials flowing therethrough. Therefore, the conditioning rolls, which are normally yieldably separable to accept thicker mats of material when necessary, will tend to aggressively condition those materials on the surface of the bunched-up masses at opposite ends of the rolls and skip the thinner, less dense stream of materials flowing through the center thereof. Consequently, the crops dry at irregular rates in the windrow or swath, leading to poor quality hay products.
Furthermore, concentrating bunches of the materials at opposite ends of the conditioning rolls leads to premature wear of the rolls at those locations which contributes to improper conditioning and precipitates earlier than desired replacement of the rolls by the farmer. These problems are even further exacerbated where the crops being harvested are tall, tough, stemmy and tangled materials.